Gifford reports that in his time “the great majority of competent and impartial critics” considered Greek to be the original language. As one of these critics O. F. Fritzsche put it, “If any one of the Apocryphal books was composed in Greek, this certainly was.” The strongest dissenter from this majority view was C. J. Ball, who marshalled the most compelling argument for a Hebrew original.
However, Yale Semitic scholar C. C. Torrey was not persuaded: “If the examination by a scholar of Ball’s thoroughness and wide learning can produce nothing better than this, it can be said with little hesitation that the language was probably not Hebrew.” Torrey’s own conclusion was that the work was originally composed in Aramaic. In recent years the tide of opinion has shifted and now the consensus is that the “letter” was originally composed in Hebrew (or Aramaic).
The date of this work is uncertain. Most scholars agree that it is dependent on certain biblical passages, notably Isa 44:9–20, 46:5–7, and thus can be no earlier than 540 BC. Since a fragment (7Q2) was identified among the scrolls in Qumran Cave 7, it can be no later than 100 BC. Further support for this terminus ad quem may be found in a possible reference to the letter in 2 Maccabees 2:1–3.
As mentioned above, the use of “seven generations” rather than “seventy years” points to a later period. Ball calculates the date to be c. 307 – 317 BC. And Tededche notes: “It is well known that many Jews were attracted to alien cults throughout the Greek period, 300 BC onward, so that the warning in the letter might have been uttered any time during this period.”
Although the “letter” is included as a discrete unit in the Septuagint, there is no evidence of it ever having been canonical in the Masoretic tradition.